Feed collet



April 15 1924.

c. J. FANCHER ET AL,

FEED LOLLE'I' Filed Jan. 19 1922 5w C'Jj'mc 736K it atented Apr, 15), 1924.

"at t CHARLES J. FANCHER AND ROBERT A. JOHNSON, OF WINDSOR, VERMONT, ASSIGNORS TO THE NATIONAL ACME COMPANY, OF CLEVELAND, OHIO, A CORPGEATTQH OF OHIO.

FEED COLLET.

Application filed January 19, 1922.

To all whom it may concern:

Be it known that we, CHARLES J. FANCHER and ROBERT A. JOHNSON, citizens of the United States, both residing at Windsor, in the county of \Vindsor and State of Vermont, have invented certain new and useful Improvements in Feed Oollets, of which the following is a specification.

This invention relates to feed collets or pusher-s adapted particularly for use in Various types of machines such as metal working machines including automatic or hand operated screw machines, bar forming machines and the like, and constructed particularly for the purpose of gripping and feeding the stock or work, an object of the in vention being to provide a feed collet having the working ends thereof bent, flared or tapered outwardly so as to permit the working ends of the collet or device to be reciprocated or shifted relatively to the end of the stock bar or work without the danger of the ends of the device contacting or striking the end of the stock, such resulting often in bending or breaking off the ends of the gripping fingers or otherwise rendering the device inoperative or useless, and resulting in considerable expense and loss of time due to the necessity of replacement and stoppage of the machine.

A further object of this invention is to provide a feed collet of this general type having gripping portions terminating in flaring or outwardly bent guide members, the construction being such that at certain times, when the device which is attached to the feed tube is reciprooated backwardly and forwardly over the end of the stock bar thereby feeding the same forwardly, the flaring ends form guides which accommodate the device to any changes in position of the stock bar resulting for instance from vibrations in the operation of the machine. Thus, by virtue of this improved construc tion, the necessity of exact alinement of the bore of the collet and the stock is obviated and the danger of the feed collet when fed forward striking the end of the stock bar is eliminated.

Other objects of this invention will appear in the following description thereof, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters indicate Serial No. 530,292.

' blank from which the collet may be formed.

The present improved feed collet is preferably formed or rolled up from a metal blank 9, struck from or stamped out of a piece of sheet metal, such as a pressedsteel plate. The blank it will be noted. comprises preferably a body portion 10 and a plurality of finger pieces 11 extending or projecting from one of the sides of the body. In the present instance the finger pieces 11 have tapered formations, but of course it will be understood that the same may be shaped in any desired manner in accordance with the preferred shape or construction of the collet.

formed or rolled up by the application of suitable pressure into a shape substantially similar to that illustrated in the drawings. The body part 10 is thus formed into a substantially tubular, hollow or cylindrical form having an endwise extending non drilled bore therethrough. The contiguous edges 19 and 20 are thus bent into juxtaposition andmay, if desired, be connected in any suitable manner, such for instance as illustrated in our copending applications, Serial No. 358,501, filed Feb. 13, 1920 now Patent No. 1,433,882, dated October 31, 1922, and Serial No. 417,646, filed Oct. 18, 1920 now Patent No. 1,433,878, dated October 31, 1922, for feed collets, and method of making feed collets respectively. The finger pieces 11 are bent, pressed, or otherwise forced in- Wardly or shaped in any suitable manner so as to form gripping fingers 12 terminating in gripping portions 13 shaped to conform tfo 1the shape of the work to be gripped or er. ping fingers 12 are highly resilient and are separated by suitable slots 14. In order to permit the attachment of the collet to the feed tube or other supporting member of the machine, the end of the collet is threaded as indicated at 15 and a shoulder 16 is formed in a suitable maner. As indicated in Fig. 4 the blank may be ofi-set at 17 to form such shoulder whereby upon rolling up or coiling the blank, the shoulder 16 will be provided. In this manner more metal will be left un- ATES PATENT OFFHGE.

It will be noted that the several gripder the threads thereby strengthening the body of the collet, than would otherwise be the case if the shoulder were formed by turning down on the outside prior to threading.

The working ends of the collet adjacent to the gripping portions 13 thereof are bent or flared outwardly as indicated at 18 thereby providing between such bent or flared portions a tapered bore, the largest diameter of which is greater than the diameter of the bore between the gripping portions 13, and also greater than the diameter of such portions and is shown extending beyond the outside of the adjacent portion of the collet, and in the present instance each flaring portion is transversely curved and therefore forms a concavo-convex guide end. Thus the outwardly bent or tapered ends 18 form guide members which permit the collet to be shifted upon the end of the stock bar or work without the danger of the ends of the collet striking the work on account of discrepancies in the alinement of the bore of the collet and the work.

As a result of this construction we have provided an improved feed collet preferably formed from a metal blank bent or shaped into a hollow body having juxtaposed edges and a preferably non-drilled bore, the collet having a gripping portion with the working end thereof bent outwardly to form an enlarged tapering guideway or opening for receiving the work. Hence by virtue of this improvement the life of the collet is greatly increased, the danger of injury thereto, as heretofore pointed out, is eliminated, the costs of operation reduced,and these without materially increasing the cost of the collet.

In practice when the collet is reciprocated back and forth with the feed tube to feed the stock to the tools, as this stock is usually in long bars, it follows that after the bar has been completely fed through the collet to the tools, the rear or tail end of the bar having left the forward end of the collet is in such position that when the collet comes forward again, it not infrequently strikes the rear end of the stock bar, thus amming the collet and. when they have been drilled from solid stock breaking off the fingers, and when made from sheet metal bending the fingers out of shape. By providing the flaring end however, the for- 1 ward edges of the collet centralize the ear of the bar and thus the longevity and durability of the collet are increased.

Although we have described our invention in its preferred form, it is to be understood that we do not limit ourselves to the construction herein shown and described except in so far as described in the claims and embraced within the scope thereof.

We claim as our invention:

1. A feed collet comprising a body portion terminating in an outwardly bent working end.

2. A feed collet comprising a body portion having a plurality of gripping portions terminating each in an outwardly bent end.

3. A feed collet comprising a body portion terminating in an outwardly flared end extending beyond the outside of the adjacent portion of the collet.

a. A feed collet comprising a body portion having a plurality of resilient gripping fingers terminating each in a gripping portion having an outwardly flared end extending beyond the outside of the adjacent portion of the collet.

5. A feed collet comprising a body portion, gripping members extending therefrom and provided with gripping portions having a bore therethrough, said members having outwardly bent portions to provide a tapered bore.

6. A feed collet comprising a metal blank bent or shaped into a hollow body portion, resilient gripping members extending therefrom and forming a gradually tapering bore terminating in a bore shaped to conform to the shape of the work to be gripped, said last part terminating in an outwardly flared portion providing a tapered bore.

7. A feed collet for a machine comprising a metal blank bent or shaped into a hollow body having a lengthwise extending bore, and a gripping portion adapted to grip the work, said gripping portion terminating in an outwardly bent transverse 1y curved end.

8. A feed collet for a machine comprising a body portion having means for attachment to a support, and also having a plurality of resilient spaced gripping members forming gripping portions. said collet at one end being bent outwardly to form a tapered opening having concavo-convex walls.

Signed at lVindsor, Vermont, this 16th day of January, 1922.

CHARLES J. FANCHER. ROBERT A. JOHNSON.

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